package com.seig.canteensystem.filter;

import com.alibaba.fastjson.JSON;
import com.seig.canteensystem.common.BaseContext;
import com.seig.canteensystem.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否已经完成登录
 */

@WebFilter(filterName = "loginCheckFiler" , urlPatterns = "/*")
@Slf4j
public class loginCheckFilter implements Filter {
    //路径匹配器，支持通配符
    public static final AntPathMatcher ANT_PATH_MATCHER = new AntPathMatcher();

    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1.获取本次请求的URI
        String requestURI = request.getRequestURI();

        log.info("拦截到请求{}",requestURI);

        //2.本次请求是否需要处理
        //2.1不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login"
        };

        boolean check = check(urls, requestURI);

        //3.如果不需要处理,则直接放行
        if(check){
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }

        //4.1.判断登录状态，如果登录，则直接放行
        if(request.getSession().getAttribute("employee")!=null){
            log.info("用户已登录,用户ID为{}",request.getSession().getAttribute("employee"));

            Long empId = (Long)request.getSession().getAttribute("employee");

            BaseContext.setCurrentId(empId);
            filterChain.doFilter(request,response);
            return;
        }

        //4.2.判断移动端登录状态，如果登录，则直接放行
        if(request.getSession().getAttribute("user")!=null){
            log.info("用户已登录,用户ID为{}",request.getSession().getAttribute("user"));

            Long userId = (Long)request.getSession().getAttribute("user");

            BaseContext.setCurrentId(userId);
            filterChain.doFilter(request,response);
            return;
        }


        log.info("用户未登录");
        //5.如果未登录则返回未登录结果,通过输出流的方式向客户端响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;


    }

    /**
     * 检查本次请求是否需要放行
     * @param requstURI
     * @return
     */
    public boolean check(String[] urls,String requstURI){
        for (String url : urls) {
            boolean match = ANT_PATH_MATCHER.match(url, requstURI);
            if(match){
                return true;
            }
        }
        return false;
    }

}
